Backing sheet for manifolding assemblies



June 1, 1937. A. M. HECK BACKING SHEET FOR MANIFOLDING .ASSEMBLIES FiledJuly 5, 1935 a- .3 IIIIIII'IIII'I''IIIIIIIIIIII IIIIIIIIIIIIIIIIIIIIIIIII Patented June 1, 1937 PATENT OFFICE BACKING SHEETFOR MANIFOLDING ASSEMBLIES Adolph M. Heck, West Los Angeles, Calif., as-

slgnor to The Columbia Carbon Company, Dayton, Ohio, a corporation ofOhio Application July 5, 1935, Serial No. 29,888

6 Claims.

10 copies may be produced, it is necessary that the impingement of'thetype upon the paper be resisted by a relatively hard platen or otherabutment surface.

Clean uniform copies of typewritten matter can .5 not be produced upon awriting machine having a rough or indented platen. To provide a smoothabutment surface against which the force of the type may be expended andwhich will insure even, strong impressions upon the overlying recordmaterial, a flexible sheet of a suitable cellu-- lose derivative isprovided preferably of acetate character and hence non-inflammable uponwhich alternating record and transfer sheets are superposed and held intheir adjusted positions by an overlapping pressure or gripper flap.

It is recognized that it is not broadly new to provide a backing sheetfor manifolding purposes of celluloid, pyroxylin or analogous material.However, much difliculty has been experienced 30 due to slipping of thebacking sheet and uneven feeding of the assembly through a writingmachine. In the present instance, mat surface areas are provided uponthe reverse face of the backing sheet for non-slipping tractionengagement with the sheet feeding devices of the writing machine.Likewise while locating tongues beneath which the writing sheets ofwriting material may be inserted have heretofore been struck from thematerial of the backing sheet 40 and in some instances the margin of apaper or other backing sheet has been sharply folded reversely for likepurpose, in the present instance the reversely folded flap is so shaped,and the fold is affected in such manner as to facilitate the engagementof the writing sheets therebeneath and enable them to be more securelyheld by the inherent tension of the overlying flap.

The object of the invention is to provide a backing sheet which may notonly be economically manufactured but which will be more efficient inuse, of convenient form, of increased durability and unlikely to get outof repair.

A further object of the invention is to pro- 55 vide improved tractionmeans for facilitating the feeding of a smooth hard surfaced sheetthrough a writing machine.

A further object of the invention is to provide a backing sheet forwriting material having gripping means for engaging writing sheets underinherent tension.

A further object of the invention is to provide a writing materialbacking sheet having a re-- versedly disposed resilient flap of improvedform and exerting pressure upon interposed writing sheets. I

With the above primary and other incidental objects in view, as willmore fully appear in the specification, the invention consists of thefeatures of construction, the parts and combinations thereof, and themode of operation, or their equivalents, as hereinafter described andset forth in the claims.

Referring to the accompanying drawing wherein is shown the preferred butobviously not neeessarily the only form of the embodiment of theinvention Fig. 1 is a perspective view of a backing sheet embodying thepresent invention with which is associated a group of writing materialsheets-assembled in writing position.

Fig. 2 is a perspective view of the backing sheet from which the writingsheets have been removed.

Fig. 3 is an enlarged sectional view.

Fig. 4 is a similar sectional view of a modification.

Like parts are indicated by similar characters of reference throughoutthe several views.

As aforestated backing sheets of celluloid, pyroxylin, paper andanalogous materials have heretofore more or less been generally used.When such backing sheets have been made of pyroxylin, celluloid or othersmooth hard surfaced materials which are most desirable for backingpurposes, considerable difliculty has been experienced due to thetendency of such materials to slip and not properly feed through awriting machine. The surface of such sheets do not ordinarily affordsufllcient traction engagement with the frictional feeding roller of atypewriter or other writing machine to efiect a uniform feedingmovement. Therefore, in the present instance, the back of the sheet hasbeen treated in. a manner as to afford improved traction efiectcontinuously throughout the length of the sheet.

If pyroxylin, celluloid or analogous sheetsare reversely folded as hasbeen the practice with paper backing sheets to form an overlapping flapfor holding the writing sheets the pyroxylin or celluloid material isquite frequently likely to a the fold line, but the resulting flap isdisposed in "converging relation with the main portion of the sheet inwhich, by its inherent tension, it exerts a gripping pressure uponinterposed sheets of writing material.

Referring to the accompanying drawing, l is the backing sheet ofpyroxylin, celluloid or analogous material but which is preferably of anacetate cellulose character and therefore non-inflammable. The topmargin of the backing sheet I is reversely folded upon itself to form awriting sheet engaging flap 2. This flap 2 extends the entire width ofthe backing sheet I and its free edge is preferably though notnecessarily of convex'curvilinear shape.

This arcuate form of the sheet holding flap greatly facilitates theinterengagement of writing sheets 3 therebeneath. The flap 2 is notsharply folded but its juncture with a the main portion of the sheet Iis through a rounded or open fold or bight 4. In the manufacture ofthese backing sheets it has been found quite desirable and efficient tofold the flap 2 over an interposed wire which will prevent tightpressing of the fold. The flap 2 beyond the bight 4 is turned throughsomewhat more than an arc of so that the flap 2 extends in a planeconvergent with that of the main portion of the backing sheet I with itsfree edge approaching the backing sheet. The converging relation of theflap 2 enables it to exert an inherent tension upon interposed writingsheets 3. Thus the writing sheets are held in assembled relation by alimited pressure or gripping effect of the flap. In this respect thepresent device differs very materially from the usually reversely foldedbacking sheet wherein the flap portionwhich is sharply folded tends toassume a divergent or gapping relation and therefore exerts no tensionor holding effect whatsoever upon the writing sheets.

In lieu of forming the overhanging gripper flap 2 from an integralportion of the backing sheet I, such flap portion may be separatelyformed and fixedly attached to the backing sheet I with a filler orspacer strip 5 interposed therebetween as shown in the detail view Fig.4. In this modified construction, while the holding flap 2 is notintegral with the backing sheet I, it is, nevertheless, fixedly securedthereto and disposed in inclined converging relation with the backingsheet and performed the same function as the integral holding flap shownin the preceding figures.

While pyroxylin, celluloid or other material having a similar hard,smooth surface is desirable for use as a backing sheet for manifoldingpurposes, such material presents a rather diflicult problem of feedingthrough the ordinary friction feed Writing machine. The frictionalfeeding rollers of the writing machine do not have suflicient tractionupon such smooth, hard material to advance it uniformly and consequentlythere is some slipping between the backing sheet and feeding rollers andthe manifolding assembly is not advanced uniformly, thereby causinguneven lines and spacing. To overcome this difficulty there are providedin the present instance mat surface stripes or areas upon the reverseside of the backing sheet I affording frictional surfaces for tractionengagement of the feeding rollers.

As a convenient and economical method of providing such mat surfacestripes 6 upon the reverse side of the sheet I, heavy lines of printersink or other frictional material are printed upon the backing sheet andat the same time a succes- 'sion of line space numbers I may be printedthereon. The printed surfaces of the line space numbers I and theparallel stripes 6 of printing ink or other frictional material affordnon-slip areas for engagement of the feeding rollers and assure uniformadvancement of the backing sheet I and the record sheet carried therebythrough the writing machine.

While for commercial production such stripes of printing ink 6 have beenfound ample and sumcient for the purpose and enable economicalproduction by passing the backing sheet I through an ordinary printingpress, it will be understood that the non-slip mat surface areas may beotherwise produced. For example, the sheet may be treated by abrasion,whereby the polished surface of the sheet is removed from certain areasand such areas given a tooth or. roughened effect by which theirfrictional engagement with the feeding rollers is materially increased.Likewise such mat surface areas may be produced by etching or byapplication of a treatment solution which will effectively remove thegloss of the sheet I and reduce its gloss surface to a friction surface.Furthermore while these frictional mat surface areas are preferablyparallel spaced stripes extending longitudinally of the backing sheet Ithey may be of other shapes and variously distributed over the reverseside of the sheet I or the entire rear face of the sheet may be treatedwith abrasive material, etching solution, or by application thereto offrictional material analogous to printer's ink. The purpose of suchtreatment in any event is to afford the necessary frictional surface toinsure uniform advancement of the backing sheet through a writingmachine by the engagement of the conventional frictional feeding rollstherewith.

A backing sheet such as heretofore described may be convenientlyinserted into an ordinary typewriter and immediately gripped between thefeeding roll and the platen roll without the necessity of relieving thetension upon the platen roll which by their contact with the frictionalmat surface areas of the back of the sheet serves to uniformly advancethe sheet through the writing machine. By reversing the holding flapthrough a rounded bight instead of sharply folding the material breakageat this point is minimized and the life of the backing sheet ismaterially extended. Moreoverv the present method avoids the necessityof holes or perforations in the backing sheets which frequently formstarting points for tears or breaks in the material.

The present form of backing sheet having the sheet gripping function isquite advantageous in the making of large numbers of manifolded copies.One of the difilculties encountered in manifolding is the tendency ofthe sheets to creep one on another or to advance ununiformly, due to theouter sheets being greater distances from the center of rotation thanthe inner sheets and hence traveling through a greater circumferentialpath. Attempts to overcome this difficulty have been made by stapling,glue spotting or otherwise flxedly attaching the sheets together. Suchfixed attachment frequently results in wrinkling of the sheets andresultant treeing of underlying sheets by carbon transfer of thewrinkles as they are fed through the machine.

It is found that the gripper flap on the present backing sheet restrainsthe creeping action and tends to maintain accurate registry ofsuperposed forms without however subjecting the sheets to wrinkling andtreeing" as occurs when the positive attachment is made.

Furthermore the convex curvilinear shape of the margin of the flapenables the sheets to be much more easily withdrawn from beneath theflap for erasing on underlying sheets without removing the assembly fromthe writing machine.

The corners of the sheets are but slightly overlapped by the iiap 2. Bycollectively grasping the margins of the sheets and pulling away fromthe backing sheet they may be readily disengaged at the corner andcontinued outward pull on the sheets produces a camming action of thesheets upon the curved edge of the flap which is progressively elevatedby the sheets which are being withdrawn. This enables one handoperation. The curvilinear form also facilitates the reinsertion of thesheets beneath the flap.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in .its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute, the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise the preferred form of several modes of putting the inventioninto effect, and the invention is therefore claimed in any of its formsor modifications within the legitimate and valid scope of the appendedclaims.

Having thus described my invention, I claim:

1. As an article of manufacture, a backing sheet for writing materialincluding a sheet member, parallel stripes of printing ink on thereverse side of the sheet affording continuous feeding traction while ina writing machine, and a record sheet holding flap on the forward sideof the sheet comprising the terminal portion of the sheet reverselyfolded upon a rounded fold line whereby the flap is directed downwardlytoward the body of the s eet.

2. As an article of manufacture for use in typewriters and the like, abacking sheet for writing material, comprising a sheet member,longitudinal parallel mat surface stripes on the reverse side of thesheet to afford continuous traction engagement with sheet feeding meansof a writing machine, and a tensioned flap upon the face of the sheetfor overlapping gripping engagement with writing sheets, said tensionedflap being an extension of a rounded fold at the terminal portion of thesheet and directed toward the sheet surface.

3. As an article of manufacture for use in typewriters and the like, abacking sheet for writing material, and relatively spaced mat surfaceareas on the reverse side of the sheet affording continuous non-sliptraction engagement with sheet feeding devices of a writing machine, theterminal portion of the sheet being reversely folded upon an arcuatefold line, and a flap extending from the arcuate fold and directedthereby into corresponding engagement with the sheet surface.

4. As an article of manufacture, a backing sheet for writing material,a, longitudinally disposed mat surface area on the back thereof fornonslip traction engagement with the feeding devices of a writingmachine and a sheet engaging flap integral therewith comprising aterminal portion of the sheet reversely folded upon itself through anarc of more than one hundred and eighty degrees whereby the flap willbear and exert pressure upon writing sheets interposed between the flapand the main portion of the backing sheet.

5. As an article of manufacture, a backing sheet for writing material, alongitudinally disposed mat surface area on the back thereof for nonsliptraction engagement with the feeding devices of a writing machine and asheet engaging flap for holding writing sheets in adjusted relationthereto, comprising an integral portion of the backing sheet reverselyfolded upon itself with an open bight, beyond which the flap assumes anormal position in a plane angularly directed relative to the plane ofthe main portion of the sheet with its free edge approaching such mainportion of the sheet to hold interposed writing sheets under tension.

6. As an article of manufacture, a backing sheet for writing material,a. longitudinally disposed mat surface area on the back thereof fornonslip traction engagement with the feeding devices of a writingmachine and an integral writing sheet holding flap having a curvilinearmarginal edge extending substantially all the way across the backingsheet from one margin to an opposite margin and comprising an integralportion of the backing sheet reversely folded upon itself about an openbight beyond which the flap converges toward the main portion of thebacking sheet with resistance to separation therefrom whereby to exertgripping pressure on writing material disposed between the flap and themain portion of the backing sheet.

ADOLPH M. HECK.

